Disk grinding machine



Feb. 28, 1950 F. P. FROE SE DI$K GRINDING MACHINE 2 Sheets-Sheet 1 FiledApril 30, .1947

P. P. FY 5 AeEr Feb. 28, 1950 F. P. FROESE DISK GRINDING MACHINE 2Sheets-Sheet 2 Filed April 30, 1947 t l I l ll lqveqfor RP. ProesePatented Feb. 28, 1950 DISK GRINDING MACHINE Frank Poersch Froese,Winnipeg, Manitoba, Canada Application April 30, 1947, Serial No.744,929 4 Claims. (01. 51-173) The invention relates to grinders, andmore particularly to grinders for sharpening discs on disc plows, plowcoulters, drill discs, disc harrows, cultivators, shovels and the like.In the ordinary sharpening of these implements, the discs are usuallycompletely dismantled and sent to a blacksmith. When they arereassembled it is often found that they do not run free. This is due tothe fact that in passing over the land the various strains and stressesencountered wear the bearings and other parts. When they are taken apartand then reassembled, it is almost impossible to position the variouspieces in exactly the same place as they were originally, with theresult that binding takes place at various points due to the previousdistortion.

The principal object of the present invention is to provide a grindermechanism which will sharpen the discs, are assembled on the machine andwithout requiring their dismantling.

A further object of the invention is to provide a grinder having freemovability so that the same can be directed against the cutting edges ofthe discs as desired.

A further object of the invention is to provide a control handle for thegrinder to direct same properly against the discs to be ground and saidhandle mounted for right or left operation.

A further object of the invention is to provide a guard for the grinderwheel to protect the operator from flying particles and said guardmovable in respect to said grinder and operable by the control handle.

A still further object of the invention is to construct the device frompressed sheet metal for lightness and portability and of a simple designfor cheapness of manufacture while being sturdy enough to stand hardusage over a long period.

A still further object of the invention is to construct the grinder foroperation by either gas engine or electric motor power.

With the above important and other minor objects in view which willbecome more apparent as the description proceeds, the invention consistsessentially in the construction and arrangement of parts hereinaftermore particularly described, reference being had to the accompanyingdrawings in which:

Figure 1 is a perspective view of the machine in operation against a setof discs.

Figure 2 is an enlarged vertical sectional view through the drivingmechanism.

Figure 3 is a vertical sectional view taken on the line 3-3, Figure 2.

above mentioned, while they Figure 4 is a perspective view of the guardbearing bracket.

Figure 5 is a perspective view of the guard.

In the drawings like characters of reference indicate correspondingparts in the several figures.

A base member I is composed of sheet metal, the sides being bentdownward, as shown at 2 and the front formed in a relatively taperedshape, as at 3. The base member is supported on three castor wheels A,two being at the back and one at the front. A casing 5 is mounted on thefront portion of the base. This casing is preferably formed from sheetmetal, and with a slight upward and inward taper. The lower edges arebent inward as at 6 and are suitably bolted as at l to the base. Therear portion of this casing is vertical and closed while the frontportion is open except at the top. The front edges are provided with aslight backward slant as indicated at 8.

A pair of cast boxings 9 and [0 are mounted at the upper rear and at theupper front of the casing and on the exterior thereof. These boxings areheld thereto by bolts H passing through the casing. A ball bearing I2 ismounted within each of the boxings. These ball bearings support agrinder shaft I3 which passes lengthwise through the casing 5. Theforward end of the shaft I3 receives an abrasive wheel [4 which ismounted between a pair of clamping discs I5 which are locked to theshaft I 3 by a nut I6 screwed to the end thereof.

A guard bearing I1 is shown in Figure 4. This comprises a tubing havingan encircling edge flange I 8. The opposite end of the tubing is formedintegral with a square plate l9 having holes 20 at the corners thereof.This bearing is received over the circular portion of the boxing l0 andthe bolts II holding said boxing pass through the holes 20 in thebearing to retain same to the boxing. The bearing bracket I! in thisposition, extends over one of the clamping discs 15 but is clear thereofso that the grinder wheel l4 may revolve without contact. A guard 2|,shown in Figure 5, is of a semicircular shape. This guard has asemicircular hub 22 which is received on the bearing bracket while theouter edge 23 is adapted to overlie the abrasive wheel M. The flange l8of the bearing bracket prevents the guard from moving toward the wheel.This guard is indicated in dotted outline in Figure 2 to show itsrelative position on the guard bearing. The hub 22 of the guard is of aslightly larger radius than that of the guard 3 bearing H as shownexaggerated in Figure 3. This is for a purpose which will be laterdescribed.

A pair of clamping straps 24 pass around the guard bearing and over thehub 22 of the guard and the ends of these straps are fastened by bolts25 to retain the guard thereon. A control handle 26 formed from a tubeor bar is welded as at 27 to one of the clamping straps 24 and at anangle. This handle passes outward from the machine, then curves and runsparallel therewith and then curves back and is pivotally bolted at 28 tothe standard 29 extending upward from the rear of the base member I. Itwill be noticed that this pivot point is aligned with the center of thegrinder shaft it.

From the above it will be seen that due to the hub 22 being of a largerradius, the clamping members 24 press the guard bearing H ondiametrically opposite sides. At the same time, the friction of theseclamps is sufficient to hold the guard therewith so that if the handle26 is rotated over the machine to the other sid the guard will rotatetherewith on the guard bearing. Accordingly, the grinder Wheel willalways be clear for contact against the work to which it is pressed. Atthe same time, if the machine is to be used for grinding a small articleor other types of work the handle 26 can be held with onehand while theoperator can rotate the guard where desired as the friction is notsufficient to hold it rigid'to the handle. This is a very handyoonstruction where time is of the essence.

The end of the shaft l3, after passing through the boxing 9, is providedwith a V-belt pulley 38 which is fastened thereto by a cotter pin 3|. AV-belt 32 passes over this pulley and down to the drive'pulley33 carriedby the shaft of a motor. This motor may be gasoline driven, electric, orany other source-of motive power and is-suitabiy fastened as by bolts 35to the base member.

In using this machine to sharpen discs, the frame of the implement isfirst mounted on-suitable blocks so that the discs thereof are free torotate and clear of the ground. If the sh'aftof these'discs is bent toprevent such'rotation or for any other reason, a suitable crank 36 canbe attached to the shaft so that the discs can be manually rotated. Awoodenplatform 3'! is provided and placed adjacent to the discs to beground and this platform forms a convenient and smooth support for thegrinding machine so that the casters canfreel roll the machinethereover.

In operation theoperator starts themotor'and then grasps the handle 26.The grindingwheel is positioned at an angle to the periphery of thediscs and then pressed thereagainst. The frictionproduced by thegrinding action causes the disc shaft and all the other discs to'rotatethus providing a fresh surface against the abrasive wheel. Thiscontinues until that particularedge of the disc isground to theoperators satisfaction. The wheel is then moved to the next disc and theoperation repeated. When one side of the said discs have been completedthe operator then swings the handle 25 over the machine and the guardfollows. The grinder is then rolled to bring the machine to the correctangle for sharpening the other side of the discs and the abrasive wheelis then pressed thereagainst. The complete set of the discs can begrounduntil a satisfactory edge is provided and if the discs do not rotatefreely enough or too freely, a, second operator can rotate the crank 36as desiredv to accomplish the result required.

From the above it will be apparent that I have produced a very simplemachine for the purpose which fills a long felt Want by farmers ingeneral. The fact that the discs of the farm implements previouslymentioned can be ground without being removed from the machine offers atremendous saving both in time and in cost-s. The machine, beingcarefully designed from sheet metal is very cheaply constructed, islight and avoids the cost of heavy castings and has no superfluousparts. The ball bearing mountings eliminate "friction and thus permitmaximum power delivery to the grinding wheel and b providing the machinewith the V-belt drive, various types and shapes of" motors with varyingheights of drive 'sh'afts'can be mounted on the base member and quicklyconnected for driving purposes. The

control handle being mounted centrally of the drive shaft, is free to beoperated from either side of the machine so that many normallyinaccessible pointsxcan be handled with case. As

the guard'member follows the handle in its rotation, no time is lost incontacting the abrasive wheel with the work. This guard, being alsomanually rotatable permits the operator to quickly use the abrasive'Wheel for many types of work outside of the particular job for which itis designed. Very little can go Wrong with this machine and the abrasivewheel is so mounted that it can be quickly replaced when worn out.

When drill discs or plow coulters are to be ground, they have to beremoved from the machine. These discs, when on the implements,

positioned back on the machine and the pins" replaced.

What I claim as my invention is: 1. In a grinding machine having anabrasive wheel mounted on a power driven shaft and said wheel partlyencircled by a guard; means for moving said guard around said abrasivewheel,

comprising: a bail shaped control arm having the ends mounted foraligned rotation with said shaft formovement of said arm from one sideof said machine to the other; and frictional means connecting said guardwith said control arm.

Ina movable grinding machine having an abrasive wheel mounted on a powerdriven shaft and said wheel partly enclosed by a guard; means fordirecting said wheel against the work to be ground, comprising: abearing around said shaft adjacent said wheel; the hub of said guardmounted on said bearing; a bail shaped control arm having the endsthereof mounted for aligned rotation with said shaft for movement ofsaid arm from one side of said machine to the other; and. one end ofsaid arm frictionally clamped over the hubof said guard.

3. In a bearing supported abrasive wheel, having aguard partly enclosingsame; means for controlling the rotation of said guard around saidabrasive wheel, comprising: a hollow spool member secured to saidbearing, adjacent to and centrally of said abrasive wheel; a'hub on saidguard, receivable over said spool member and rotatable,

5 thereon; and a manually operable control arm clamped to said guard huband rotatable with said guard hub around said spool member.

4. A disc grinding machine, comprising: a caster supported fiat basemember having a standard projecting upwardly at one end; a hollow casingsupported on the opposite end of said base member with the upper endprojecting thereover; a shaft passing lengthwise through said upper endof said casing, mounted in end bearings thereon, and driven by a motorsupported on said base member; an abrasive wheel mounted on thecasing-projecting end of said shaft, clear of said base member; a guardpartially encircling said abrasive wheel, having a hub rotatably mountedon one of said bearings adjacent said abrasive wheel; a bail-shapedmanually operable control arm, having one end connected to said hub and.the other end pivotally mounted on said standard in alignment with saidshaft, for rotation of said bail-shaped arm from one side of said memberto the other.

FRANK POERSCH FROESE.

REFERENCES CITED The following references are of record in the file ofthis patent:

5 UNITED STATES PATENTS Number Name Date 963,437 I-Iassel July 5, 19101,134,833 Fischer et al. Apr. 6, 1915 10 1,795,262 Myers Mar. 3, 19312,286,293 Mall June 16, 1942 2,292,229 Krueger Aug. 4, 1942 2,301,264Emery Nov. 10, 1942 15 FOREIGN PATENTS Number Country Date 13,601 GreatBritain June 2, 1897 71,092 Switzerland Dec. 4, 1915

